BALTIMORE — April was miserable, and with the Yankees stepping up in class in May, things could easily get worse.

Watching the Yankees go 8-15 in the first month-plus of the season was difficult. However, the second leg consists of 28 games in 29 days — 15 on the road, 13 in The Bronx — and against teams with a combined record of 108-94, which is a .535 winning percentage, going into Monday night’s action.

They started May by watching Nathan Eovaldi, whom some were ready to anoint as a legitimate top-of-the-rotation starter after a dominating performance in Texas last week, give up a pair of two-run leads Sunday to the Red Sox in Fenway Park.

The Yankees open a three-game series Tuesday night against the banged-up Orioles at Camden Yards in the AL East cellar. They haven’t hit as a group, have yet to find a starter to consistently fall in behind ace Masahiro Tanaka, are below average defensively and are failing to deliver clutch hits.

Joe GirardiPaul J. Bereswill

Late Sunday evening, in the din of the cramped Fenway Park visitors’ clubhouse, nobody was ready to jump off a bridge, but the message from two prominent voices was serious.

“It’s a small sample size, but getting bigger,’’ Mark Teixeira said of the first 23 games. “You can’t blame it on bad luck. We have to start winning games.’’

The five-game losing streak being lugged into Camden Yards is mostly because the “Dead Bats Society’’ has squatter rights in the Yankees’ bat rack.

“It’s frustrating,’’ said Joe Girardi, whose club has dropped 13-of-18 games and is six lengths behind the AL East-leading Red Sox. “It doesn’t matter how you lose. We are in the business of winning games.’’

That was difficult in April, and the schedule doesn’t soften in May. Following three with the Orioles, the Yankees return home for a rematch with the Red Sox, four with the defending World Series champion Royals and three against the AL Central-leading White Sox. A seven-game trip opens May 16 in Arizona and continues with four in Oakland against the pedestrian A’s, who swept a three-game series from the Yankees in The Bronx last month. A three-game series with the Blue Jays at home leads into three tilts at Tampa Bay and three more at Toronto. The final game in Canada bleeds into June.

Pitching and defense, neither of which has been stellar, supposedly wins games. But you have to hit and the Yankees have seven regulars in the lower half of the 105 AL batters to qualify for the batting title. Chase Headley is last with a .156 average.

Alex Rodriguez, who is 6-for-15 (.400) with three homers and six RBIs in the last four games and qualifies as hot, looked at the seven runs Sunday night at Fenway as a building block.

“Hopefully it set the tone for us,’’ said Rodriguez, who leads the club with five homers and is tied for the RBI lead with Starlin Castro (12), despite hitting .203. “We hadn’t done what we did tonight in a long time.’’

That’s for certain. Entering Sunday night’s action, the Yankees had scored 39 runs in the previous 17 games, in which they went 5-12. That’s an average of 2.29 per game and even a staff stuffed with Cy Young winners instead of Michael Pineda and Luis Severino would have trouble winning with that paltry support.

Sunday’s seven runs — six against Red Sox ace David Price — was the most the Yankees scored since plating eight on April 9 against the Tigers.

You looked at April and said it can’t get worse. Until you glanced at the schedule and saw May, a month that could bury the Yankees if they don’t improve quickly.